The invention concerns the field of optical data transmission technology, and relates to a configuration for coupling optoelectronic elements, each having an optically active zone, to individually allocated optical waveguide sections. The optical waveguide sections are contained in a coupling element and optical coupling paths run between the optical waveguide sections and the optically active zones.
In the context of the invention, an optoelectronic element should be taken to be a transmitter or a receiver. When driven electrically, an optoelectronic element configured as a transmitter converts the electrical signals into optical signals, which are emitted in the form of light signals. When optical signals are applied to it, an optoelectronic element configured as a receiver converts them into corresponding electrical signals that can be taken from the output. The region of an optoelectronic element where the aforementioned signal conversions take place will also be referred to below as the optically active zone.
Further, an optical waveguide is understood as being any device for the guided delivery of an optical signal over a substantial distance in space, in particular preassembled optical waveguides and other xe2x80x9cwave guidesxe2x80x9d.
The region within which the optical signals travel between the optically active zone and the input or output position of an optical waveguide section, which is individually allocated just to the zone, while freely propagating through air and/or another medium that is optically transparent in the wavelength range used and/or through imaging optical elements, will be referred to below as the optical coupling path.
German Patent DE 197 05 042 C1 discloses a coupling configuration of the type described in the introduction, in which e.g. twelve parallel optical waveguide sections (fibers) are disposed between two high-accuracy bores for alignment pins and are coupled to optoelectronic elements that are individually allocated to them. A support contains structured recesses, into which the optical waveguide sections are fitted, and reflecting surfaces for deflecting light.
PCT Patent Application PCT/DE99/01959 describes a multiple optical jack (ferrule). The ferrule has a jacket casing with two holding regions for holding optical waveguide sections. The holding regions are disposed above one another as viewed in the insertion direction. In order to connect two jacket casings, guide bores for guide pins may be provided extending in the insertion direction.
U.S. Pat. No. 5,230,030 discloses a system for coupling a plurality of optical waveguide sections, which are guided in a plurality of planes, to semiconductor chips. U.S. Pat. No. 5,230,030 does not provide any further details about the respective allocation of the optical waveguide to the semiconductor chips.
It is accordingly an object of the invention to provide a configuration for coupling optoelectronic elements and fiber arrays which overcomes the above-mentioned disadvantages of the prior art devices of this general type, in which a large number of optical waveguide sections are coupled in a narrow space to individually allocated optoelectronic elements.
With the foregoing and other objects in view there is provided, in accordance with the invention, a coupling configuration. The coupling configuration contains optoelectronic elements having optically active zones, a coupling element, and optical waveguide sections for coupling to each of the optoelectronic elements. The optical waveguide sections are disposed in the coupling element, and the optical waveguide sections are disposed in at least two planes including a first plane and a second plane. The optical waveguide sections of different ones of the two planes are offset in relation to one another. Optical coupling paths run between the optical waveguide sections and the optically active zones. At least some of the optical coupling paths allocated to the optical waveguide sections of the first plane pass through intermediate spaces that exist between the optical waveguide sections of the second plane.
The object is achieved according to the invention, in the case of a configuration of the type mentioned in the introduction, by the fact that the optical waveguide sections are disposed in at least two planes so that at least some of the coupling paths allocated to the optical waveguide sections of one plane pass through intermediate spaces that exist between optical waveguide sections of the other plane.
By disposing the optical waveguide sections in a plurality of planes, it is possible to couple a large number of optical waveguide sections with optoelectronic elements allocated individually to them, without interference, with lower loss and without extending the coupling configuration. It is therefore possible to continue using geometries that have become established on the market (e.g. the distances of the positioning devices). The spacing (separation) of the optical waveguide sections in the individual planes allows the coupling paths, which are allocated to the optical waveguide sections of one plane, to run through intermediate spaces between the optical waveguide sections of the other plane. In this way, it is possible to couple a large number of optical waveguide sections with optoelectronic elements allocated individually to them, with a simple and compact configuration.
One embodiment of the configuration, which is particularly advantageous in terms of manufacturing technology, is distinguished by the fact that the optical waveguide sections lying in a common plane are spaced apart from one another at a constant separation, and the optical waveguide sections of different planes are offset in relation to one another.
With a view to a simple and compact configuration of the coupling paths between the optical waveguide sections and the optoelectronic elements, a further advantageous configuration of the configuration according to the invention proposes that the coupling-side end surfaces of the optical waveguide sections be ground at an angle and polished and, for example, carry a reflective coating.
With a view to particularly accurate and reliable fixing of the optical waveguide sections in the coupling element, in a preferred refinement of the invention, the coupling element contains a precision part and two slide members, which fix the optical waveguide sections in the precision part.
In addition to this, the optical waveguide sections and the slide members may be adhesively bonded in their intended position.
A further embodiment of the configuration according to the invention, which is favorable in terms of construction and saves on material, proposes that a part of the precision part protrude beyond the optoelectronic elements in the manner of a collar support.
Particularly low-loss coupling is possible, according to a further embodiment of the invention, if the coupling element has material recesses in the vicinity of the optical coupling paths.
In terms of manufacturing technology, it is particularly preferable and cost-effective to use a coupling element that is formed of a plastic and is made by precision injection molding.
A further advantageous embodiment is characterized in that the optoelectronic elements are fitted on at least one support, and the optically active zones of the optoelectronic elements are disposed in at least two rows.
With a view to simple attachment of the electrical drive system to the optoelectronic elements, the support may have electrical contacts and interconnections with the optoelectronic elements. In addition to this, the coupling element and the support may be mounted on a common casing circuit board.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a configuration for coupling optoelectronic elements and fiber arrays, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.